kernel: Incorrect Conversion between Numeric Types
CVE-2022-2639 is a high-severity incorrect conversion between numeric types vulnerability in kernel, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. Affected kernel versions: kernel 5.18. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.92% chance of exploitation within 30 days, higher than 61% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux Kernel to 3.19 or 4.5 or 4.9.312 or 4.14.277, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Kernel | kernel | kernel 5.18 | Not stated |
| Linux | Linux Kernel | 3.18.139 up to, but not including, 3.19; 4.4.179 up to, but not including, 4.5; 4.9.169 up to, but not including, 4.9.312; 4.14.112 up to, but not including, 4.14.277; 4.19.35 up to, but not including, 4.19.240; 5.0.8 up to, but not including, 5.4.191; 5.5 up to, but not including, 5.10.113; 5.11 up to, but not including, 5.15.36; and 1 more ranges | 3.19, 4.5, 4.9.312, 4.14.277, 4.19.240, 5.4.191 |
| Red Hat | Enterprise Linux | 8.0; 9.0 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
Official description
An integer coercion error was found in the openvswitch kernel module. Given a sufficiently large number of actions, while copying and reserving memory for a new action of a new flow, the reserve_sfa_size() function does not return -EMSGSIZE as expected, potentially leading to an out-of-bounds write access. This flaw allows a local user to crash or potentially escalate their privileges on the system.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Conversion between Numeric Types
When converting from one data type to another, such as long to integer, data can be omitted or translated in a way that produces unexpected values. If the resulting values are used in a sensitive context, then dangerous behaviors may occur.
How developers prevent this class of flaw
- Avoid making conversion between numeric types. Always check for the allowed ranges.
More Incorrect Conversion between Numeric Types vulnerabilities (CWE-681)
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- bugzilla.redhat.com/show_bug.cgi?id=2084479Issue Tracking, Third Party Advisory
- github.com/torvalds/linux/commit/cefa91b2332d7009bc0be5d951d6cbbf349f90f8Exploit
Other vulnerabilities in kernel
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- 7.1 High severity
- 8.1 High severity
- 8.1 High severity
Recent Incorrect Conversion between Numeric Types vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
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